question about 82 engine in my 83
 

i swapped my 82 engine (12a) into my 83 and well i am kinda getting tired of this back fire or whatever it is but when shifting,i get this pop pop pop,and when letting off the gas without the clutch in it doesnt feel like its running smoothely... and well when we first go the engine done it wasnt running right it would not stay running and it would shutter like the timing was off... so we took it out and drove it a little and i pushed the throttle to the floor and at 5k rpms it would take off like a rocket so i opened the air cleaner and plugged one of the holes and it would run fine idk whats going on plz help thanx

no reply hmm stumped too huh ok please help lol